1. Field of the Invention
The present invention relates to a shelf of laminated material, particularly of sheet metal. The shelf has downwardly bent edges at the sides thereof, particularly at the longitudinal sides. The downwardly bent edges form stiffening portions which over the width thereof have cross-sectional profiles which are at least partially open toward the center of the shelf.
2. Description of the Prior Art
Shelves of this type are already known and have been in practical use for a long time.
Depending upon the required stability and stiffness, these known shelves are made of sheet metal blanks of different thicknesses. In order to increase the stability of the shelves of this type, they have been provided with stiffening sections, particularly at the longitudinal sides of the shelves. These stiffening sections have a cross-sectional shape of a closed pipe, such as, a square pipe. These shelves additionally have an end flange provided outside of the pipe section at the underside of the shelf. This end flange is attached to the shelf at the underside thereof by means of, for example, spot welding.
In a shelf of the type descried above disclosed German Offenlegungsschrift No. 31 24 922, stiffening sections are provided which are formed by downwardly bent edges. The stiffening sections include two parallel pipe sections which are held spaced apart from each other by means of a downwardly open channel section. The spaced-apart walls of the pipe sections which face each other simultaneously form the webs of the channel section.
In another shelf of laminated material disclosed in German Offenlegungsschrift No. 34 41 500, the cross-section of the pipe forming the stiffening section has at least at its lower, inwardly facing longitudinal rim an outwardly facing sectional portion which is formed by a step-like bent edge.
In all of the prior art shelves discussed above, the shelf proper and the stiffening sections provided at the shelf are made of the same laminated material, particularly sheet metal. The selection of the thickness of the laminated material is in direct relation to the desired or required stability of the stiffening sections, so that the entire shelf has this material thickness. However, in most cases, it would be completely sufficient to use a shelf in which the shelf proper has a reduced thickness in order to save material.
It is, therefore, the primary object of the present invention to provide a shelf of laminated material of the type described above in which the construction of the shelf and especially the stability and load bearing capacity thereof can be adapted without problems to different requirements.